Trifluoromethanesulfonanilide compounds and herbicidal compositions containing them

ABSTRACT

A trifluoromethanesulfonanilide compound having the formula: ##STR1## wherein Y is a (1-cyano-2-propyl)cyclopropyl group or a (1-cyano)cyclopentyl group.

This is a continuation-in-part application of Ser. No. 871,870, filed on June 9, 1986, now U.S. Pat. No. 4,659,371.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to novel trifluoromethanesulfonanilide compounds and herbicidal compositions containing them as active ingredients.

2. Discussion of Background

In recent years, many herbicides have been developed and practically used, and they have contributed to the saving of the labor force for the agricultural work and to the improvement of the productivity.

However, in the practical use, these herbicides have various problems in respect of the herbicidal activities and safety, and development of further improved herbicides is desired.

U.S. Pat. No. 3,639,474 discloses that certain trifluoromethanesulfonanilide compounds have herbicidal activities. However, the compounds disclosed in this U.S. patent have drawbacks that their herbicidal activities are rather poor against perennial weeds, and further their safety against cotton is rather low.

SUMMARY OF THE INVENTION

The present inventors have conducted extensive researches to solve such problems, and as a result, have found that the trifluoromethanesulfonanilide compounds of the formula I as defined hereinafter exhibit excellent herbicidal effects against perennial weeds such as Johnsongrass (Sorghum halepense) and purple nutsedge (Cyperus rotundus) and superior safety against cotton, as compared with the compounds disclosed in the above-mentioned U.S. patent, and they have a high level of safety also against a sunflower (Helianthus annuus). The present invention has been accomplished on the basis of this discovery.

The patent application Ser. No. 871,870 is directed to a trifluoromethanesulfonanilide compound having the formula: ##STR2## wherein each of R¹ and R² is a lower alkyl group, X is a halogen atom or a trifluoromethyl group, n is an integer of 0 to 2, and R¹ and R² may form, together with the adjacent carbon atom, a ring which may be substituted by a lower alkyl group.

The compound of the formula I can be prepared by reacting an aniline derivative having the formula: ##STR3## wherein R¹, R², X and n are as defined above, with trifluoromethanesulfonic acid anhydride or a trifluoromethanesulfonic acid halide.

The present invention provides a trifluoromethanesulfonanilide compound having the formula: ##STR4## wherein Y is a (1-cyano-2-propyl)cyclopropyl group or a (1-cyano)cyclopentyl group.

More specifically, the present invention is directed to a trifluoromethanesulfonanilide compound having the formula: ##STR5## wherein Y is a (1-cyano-2-propyl)cyclopropyl group or a (1-cyano)cyclopentyl group.

The compounds of the formulas I' and I" may be prepared in the same manner as the preparation of the compound of the formula I.

The present invention also provides a herbicidal composition comprising a herbicidally effective amount of the compound of the formula I' and an agricultural adjuvant.

Further, the present invention provides a method for killing weeds which comprises applying a herbicidally effective amount of the compound of the formula I to a locus to be protected.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the formulas I and II, each of R¹ and R² is a lower alkyl group, preferably a methyl group or an ethyl group. Otherwise, R¹ and R² may form, together with the adjacent carbon atom, a ring which may be substituted by a lower alkyl group, such as a cyclopropyl group, a cyclopentyl group, a methylcyclopropyl group or an ethylcyclopropyl group.

X is a halogen atom such as a chlorine atom or a fluorine atom, or a trifluoromethyl group.

Specific examples of the compounds of the formula I will be presented in Table 1. The compound numbers will be referred to in the subsequent description.

                                      TABLE 1                                      __________________________________________________________________________      ##STR6##                                                                                          Melting point (°C.)                                                     Boiling point (°C./                                 Compound            mmHg), or Refrac-                                          No.   Xn    Y       tive index (n.sub.D.sup.20)                                __________________________________________________________________________     1     H                                                                                     ##STR7##                                                                              mp 118-120                                                 2     2-Cl                                                                                  ##STR8##                                                                              mp 92-93                                                   3     3-Cl                                                                                  ##STR9##                                                                              mp 140-142                                                 4     2-CF.sub.3                                                                            ##STR10##                                                                             mp 133-137                                                 5     2-Cl                                                                                  ##STR11##                                                                             bp 122-126/0.025 ri 1.4951                                 6     2,4-Cl.sub.2                                                                          ##STR12##                                                                             mp 115-116                                                 7     2-F, 4-Cl                                                                             ##STR13##                                                                             mp 131-133                                                 8     2,4-F.sub.2                                                                           ##STR14##                                                                             mp 112-113                                                 9     H                                                                                     ##STR15##                                                                             mp 104-105                                                 10    H                                                                                     ##STR16##                                                                             mp 128-130                                                 11    H                                                                                     ##STR17##                                                                             mp 133-135                                                 12    2-Cl                                                                                  ##STR18##                                                                             mp 88-93                                                   13    2-Cl                                                                                  ##STR19##                                                                             mp 115-118                                                 14    2-F                                                                                   ##STR20##                                                                             mp 99-103                                                  15    2,4-Cl.sub.2                                                                          ##STR21##                                                                             mp 168-169                                                 16    2,4-Cl.sub.2                                                                          ##STR22##                                                                             mp 161-163                                                 17    4-Cl                                                                                  ##STR23##                                                                             mp 113-119                                                 18    2,5-Cl.sub.2                                                                          ##STR24##                                                                             ri 1.5219                                                  19    3-Cl                                                                                  ##STR25##                                                                             mp 112-114                                                 20    2,4-Cl.sub.2                                                                          ##STR26##                                                                             mp 152-155                                                 21    2,4-Cl.sub.2                                                                          ##STR27##                                                                             mp 124-127                                                 22    2,4-Cl.sub.2                                                                          ##STR28##                                                                             mp 87.5-88                                                 __________________________________________________________________________

The compounds of the present invention represented by the formula I can be prepared by a process which comprises reacting an aniline derivative of the formula II with trifluoromethanesulfonic acid anhydride or a trifluoromethanesulfonic acid halide in the presence or absence of a solvent such as acetone, methyl ethyl ketone, dimethylformamide, dimethylsulfoxide, tetrahydrofuran, benzene, toluene, xylene, chlorobenzene, chloroform, dichloromethane or carbon tetrachloride, in the presence or absence of an organic or inorganic base, for example, an alkali metal carbonate such as sodium hydroxide, potassium carbonate or sodium hydrogen carbonate or a tertiary amine such as triethylamine, dimethylaniline or pyridine, at a temperature of from -15° to 100° C. for from 1 to 20 hours.

Now, the process for the production of the compounds of the present invention will be described in detail with reference to Examples.

PRODUCTION EXAMPLE 1 (COMPOUND NO. 5) Production of 2-chloro-5-(1-cyano-1-methyl)-ethyltrifluoromethanesulfonanilide

Into a 100 ml reaction flask equipped with a thermometer, a dropping funnel and a nitrogen supply tube, 2.9 g (0.015 mol) of 2-chloro-5-(1-cyano-1-methyl) ethylaniline, 1.5 g (0.015 mol) of triethylamine and 50 ml of dichloromethane were introduced, and 5.0 g (0.018 mol) of trifluoromethanesulfonic acid anhydride was gradually dropwise added under nitrogen pressure at 0° C. under stirring. After the completion of the dropwise addition, the stirring was continued at room temperature for 3 hours. The reaction solution was washed three times with 30 ml of 10% hydrochloric acid and further with water, and then dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure. The residue thus obtained was distilled under reduced pressure to obtain 3.5 g of 2-chloro-5-(1-cyano-1-methyl) ethyl trifluoromethanesulfonanilide as a light yellow transparent viscous liquid of a fraction having a boiling point of from 122° to 126° C./0.025 mmHg. The refractive index N_(D) ²⁰ was 1.4951.

PRODUCTION EXAMPLE 2 (COMPOUND NO. 10) Production of 4-(1-cyano)cyclopropyltrifluoromethane sulfonanilide

Into a 100 ml reaction flask equipped with a thermometer, a dropping funnel and a nitrogen supply tube, 3.1 g (0.02 mol) of (1-cyano)cyclopropylaniline, 1.7 g (0.022 mol) of pyridine and 50 ml of dichloromethane were introduced, and 6.2 g (0.022 mol) of trifluoromethanesulfonic acid anhydride was gradually dropwise added under nitrogen pressure at 0° C. under stirring. After the completion of the dropwise addition, the stirring was continued at room temperature for 4 hours. The reaction solution was washed three times with 30 ml of 10% hydrochloric acid and further with water, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure. The crude crystals thus obtained were recrystallized from ethanol to obtain 4.8 g of 4-(1-cyano)cyclopropyltrifluoromethanesulfonanilide as a yellow brown powder having a melting point of from 128° to 130° C.

PRODUCTION EXAMPLE 3 (COMPOUND NO. 15) Production of 2,4-dichloro-5-(1-cyano)cyclopropyl trifluoromethanesulfonanilide

Into a 100 ml reaction flask equipped with a thermometer, a dropping funnel and a nitrogen supply tube, 2.7 g (0.012 mol) of 2,4-dichloro-5-(1-cyano) cyclopropylaniline, 1.3 g (0.013 mol) of triethylamine and 50 ml of dichloromethane were introduced, and 3.7 g (0.013 mol) of trifluoromethanesulfonic acid anhydride was gradually dropwise added under nitrogen pressure at 0° C. under stirring. After the completion of the dropwise addition, the stirring was continued at room temperature for 4 hours. The reaction solution was washed three times with 30 ml of 10% hydrochloric acid and further with water, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure. The crude crystals thus obtained was washed with n-hexane to obtain 2.6 g of 2,4-dichloro-5-(1-cyano)cyclopropyltrifluoromethanesulfonanilide as colorless crystals having a melting point of from 168° to 169° C.

Compound Nos. 1 to 4, 6 to 9, 11 to 14 and 16 to 20 were prepared in the manners similar to the above Examples.

PRODUCTION EXAMPLE 4 (COMPOUND NO. 22) Production of 2,4-dichloro-5-(1-cyano)cyclopentyl trifluoromethanesulfonanilide

Into a 100 ml reaction flask equipped with a thermometer, a dropping funnel and a nitrogen supply tube, 3.8 g (0.015 mol) of 2,4-dichloro-5-(1-cyano) cyclopentylaniline, 2.0 g (0.02 mol) of triethylamine and 50 ml of dichloromethane mol) of trifluoromethanesulfonic acid anhydride was gradually dropwise added under nitrogen pressure at 0° C. under stirring. After the completion of the dropwise addition, the stirring was continued at room temperature for 3 hours. The reaction solution was washed three times with 30 ml of 10% hydrochloric acid and further with water, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure. The crude crystals thus obtained was recrystallized from ethanol to obtain 1.8 g of 2,4-dichloro-5-(1-cyano)cyclopentyltrifluoromethanesulfonanilide as colorless crystals having a melting point of from 87.5° to 88° C.

PRODUCTION EXAMPLE 5 (COMPOUND NO. 21) Production of 2,4-dichloro-5-(1-cyano-2-propyl)cyclopropyl trifluoromethanesulfonanilide

Into a 100 ml reaction flask equipped with a thermometer, a dropping funnel and a nitrogen supply tube, 4.0 g (0.015 mol) of 2,4-dichloro-5-(1-cyano-2-propyl)cyclopropylaniline, 2.0 g (0.02 mol) of triethylamine and 50 ml of dichloromethane were introduced, and 5.6 g (0.02 mol) of trifluoromethanesulfonic acid anhydride was gradually dropwise added under nitrogen pressure at 0° C. under stirring. After the completion of the dropwise addition, the stirring was continued at room temperature for 4 hours. The reaction solution was washed three times with 30 ml of 10% hydrochloric acid and further with water, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure. The crude crystals thus obtained was washed with n-hexane to obtain 1.3 g of 2,4-dichloro-5-(1-cyano-2-propyl)cyclopropyltrifluoromethanesulfonanilide as yellow crystals having a melting point of from 124° to 127° C.

The compounds of the present invention may be used as herbicides by themselves or in combination with agricultural adjuvants such as a carrier, a surface active agent, a dispersant, an assisting agent, etc. in the form of various formulations such as wettable powders, granules, emulsifiable concentrates or dusts.

As the carrier used for the formulation, there may be mentioned a solid carrier such as talc, bentonite, clay, kaoline, diatomaceous earth, white carbon, vermiculite, slaked lime, silica, ammonium sulfate or urea, or a liquid carrier such as isopropylalcohol, xylene or cyclohexane. As the surface active agent and dispersant, there may be mentioned, for instance, a sulfate of an alcohol, an alkyl sulfonate, a lignin sulfonate, a polyoxyethylene glycol ether, a polyoxyethylene alkyl aryl ether, or a polyoxyethylene sorbitan monoalkylate. As the assisting agent, for instance, carboxymethyl cellulose, polyethylene glycol or gum arabic may be mentioned. In the actual application, the herbicidal composition may be applied directly or after being diluted to a proper concentration.

Now, Formulation Examples for the herbicidal composition of the present invention will be described. However, it should be understood that the present invention is by no means restricted to these specific Examples.

FORMULATION EXAMPLE 1 (GRANULES)

10% by weight of Compound No. 1, 2% by weight of sodium salt of a lauryl alcohol sulfuric acid ester, 5% by weight of sodium lignin sulfonate, 2% by weight of carboxymethyl cellulose and 81% by weight of clay were uniformly mixed and pulverized. To 80 parts by weight of this mixture, 20 parts by weight of water was added, and the mixture was kneaded. The kneaded mixture was granulated by an extrusion type granulating machine and dried to obtain granules of from 14 to 32 mesh.

FORMULATION EXAMPLE 2 (GRANULES)

2% by weight of a sodium salt of a lauryl alcohol sulfuric acid ester, 5% by weight of sodium lignin sulfonate, 2% by weight of carboxymethyl cellulose and 91% by weight of clay were uniformly mixed and pulverized. To 78 parts by weight of this mixture, 22 parts by weight of water was added, and the mixture was kneaded. The kneaded mixture was granulated by an extrusion type granulating machine and dried to obtain granules of from 14 to 32 mesh as adsorptive substrate. To 80 parts by weight of this substrate, 20 parts by weight of a solution comprising 40% by weight of Compound No. 3 and 60% by weight of polyethylene glycol, was uniformly adsorbed to obtain granules.

FORMULATION EXAMPLE 3 (EMULSIFIABLE CONCENTRATE)

30% by weight of Compound No. 10, 20% by weight of cyclohexane, 11% by weight of polyoxyethylene alkyl aryl ether, 4% by weight of calcium alkylbenzene sulfonate and 35% by weight of methyl naphthalene, were uniformly dissolved to obtain an emulsifiable concentrate.

FORMULATION EXAMPLE 4 (WETTABLE POWDER)

10% by weight of Compound No. 15, 85% by weight of diatomaceous earth, 2% by weight of sodium dinaphthylmethane disulfonate and 3% by weight of sodium lignin sulfonate were uniformly mixed and pulverized to obtain a wettable powder.

FORMULATION EXAMPLE 5 (DUST)

4% by weight of Compound No. 16, 5% by weight of diatomaceous earth and 91% by weight of clay were uniformly mixed and pulverized to obtain a dust.

The trifluoromethanesulfonanilide compounds of the present invention represented by the formula I, are capable of controlling a number of weeds grown in paddy rice fields by their application as herbicides for the preemergence or postemergence soil treatment in the paddy rice fields.

Further, in the case of upland fields, they are capable of controlling a number of weeds grown in the upland fields by their application for the preemergence or postemergence soil treatment or for the foliage treatment.

Namely, the compounds of the present invention can effectively control annual and perennial weeds grown in paddy rice fields, such as Echinochloa crus-galli (barnyardgrass), Cyperus difformiss (umbrella plant), Monochoria vaginalis (monochoria), Scirpus juncoides (hardstem bulrush), Cyperus serotinus (flat sedge) and Alisma gramineum (narrowleaf waterplantain).

Further, they are capable of effectively controlling annual and perennial weeds grown in upland fields, such as Echinochlor crus-galli (barnyardgrass), Digitaria sanguinalis (large crab-grass), Setaria viridis (green foxtail), Cyperus rotundus (purple nutsedge), Sorghum halepense (Johnsongrass), Polygonum lapathifolium (pale smartweed), Amaranthus retroflexus (pigweed), Chenopodium album (lamb's quaters), Chenopodium album var. centrorubrum (goosefoot), Abutilon theophrasti (velvet leaf), Ipomoea spp. (morning-glory) and Cyperus iria (flatsedge).

Moreover, the compounds of the present invention have a feature that they have far superior effectiveness against perennial weeds such as Cyperus rotundus (purple nutsedge) and Sorghum halepense (Johnsongrass), and a high level of safety against Gossypium hirstum (cotton), as compared with the compounds disclosed in U.S. Pat. No. 3,639,474, and they are highly safe against Helianthus annuus (sunflower).

When the compound of the present invention is used as a herbicide, the dose to obtain a desired level of effectiveness varies depending upon the weather condition, the soil condition, the type of the formulation, the season of the application, the method and condition of the application, the kinds of weeds, etc. However, it is usually in a range of from 0.1 to 10 kg/ha, preferably from 0.5 to 4 kg/ha.

Now, the effectiveness of the herbicidal compositions of the present invention will be described with reference to Examples.

TEST EXAMPLE 1

In 600 cm² pots, cotton seeds and rhizomes of Johnsongrass and tubers of purple nutsedge were planted and covered with soil in a depth of 1.5 cm, respectively. One day later, a wettable powder prepared in accordance with Formulation Example 4, was diluted with 1 kl/ha of water and uniformly sprayed over the surface of soil at the dose as identified in Table 2. Thirty days after the treatment, the aerial parts was examined, and the herbicidal effects were evaluated in accordance with the following standards.

The results are shown in Table 2.

    ______________________________________                                         Herbicidal                                                                     index       Herbicidal effect or phytotoxicity                                 ______________________________________                                         10          Withered completely                                                9           Herbicidal effect: at least 90% and less                                       than 100%                                                          8           Herbicidal effect: at least 80% and less                                       than 90%                                                           7           Herbicidal effect: at least 70% and less                                       than 80%                                                           6           Herbicidal effect: at least 60% and less                                       than 70%                                                           5           Herbicidal effect: at least 50% and less                                       than 60%                                                           4           Herbicidal effect: at least 40% and less                                       than 50%                                                           3           Herbicidal effect: at least 30% and less                                       than 40%                                                           2           Herbicidal effect: at least 20% and less                                       than 30%                                                           1           Herbicidal effect: more than 0% and less                                       than 20%                                                           0           No herbicidal effect                                               ______________________________________                                    

The Comparative Compounds tested for the purpose of comparison were as follows: ##STR29##

                  TABLE 2                                                          ______________________________________                                                    Dose of                                                                        active    Herbicidal index                                          Tested     ingredient                 Purple                                   compound   (kg/ha)   Cotton  Johnsongrass                                                                            nutsedge                                 ______________________________________                                         Compound   4         0       9        10                                       1          2         0       9        6                                                   1         0       6        3                                        Compound   4         1       9        10                                       2          2         1       9        9                                                   1         0       8        8                                        Compound   4         0       9        --                                       4          2         0       9        --                                                  1         0       9        --                                       Compound   4         3       9        10                                       5          2         1       9        10                                                  1         0       7        10                                       Compound   4         0       8        9                                        6          2         0       8        9                                                   1         0       6        7                                        Compound   4         0       10       --                                       10         2         0       10       --                                                  1         0       9        --                                       Compound   4         1       9        9                                        15         2         0       8        8                                                   1         0       8        6                                        Compound   4         0       7        5                                        16         2         0       6        4                                                   1         0       4        2                                        Compara-   4         5       6        8                                        tive       2         2       4        4                                        Compound 1 1         0       2        2                                        Compara-   4         6       3        6                                        tive       2         3       2        4                                        Compound 2 1         0       0        0                                        Compara-   4         0       0        0                                        tive       2         0       0        0                                        Compound 3 1         0       0        0                                        ______________________________________                                          Note:                                                                          The symbol "--" means "not tested".                                      

TEST EXAMPLE 2

In 600 cm² pots, cotton seeds and tubers of purple nutsedge were planted and covered with soil in a depth of 1.5 cm, respectively. One day layer, a wettable powder prepared in accordance with Formulation Example 4, was diluted with 1 kl/ha of water and uniformly sprayed over the surface of soil at the dose as identified in Table 3. Thirty days after the treatment, the aerial parts was examined, and the herbicidal effects were evaluated in accordance with the standards as identified in Test Example 1.

In addition to the Comparative Compounds used in Test Example 1, the following compound was tested as an additional Comparative Compound. ##STR30##

The results are shown in Table 3.

                  TABLE 3                                                          ______________________________________                                                    Dose of                                                                        active        Herbicidal index                                      Tested     ingredient            Purple                                        compound   (kg/ha)       Cotton  nutsedge                                      ______________________________________                                         Compound 17                                                                               2             1       8                                                        1             0       7                                             Compound 18                                                                               4             0       10                                                       2             0       8                                             Compound 19                                                                               4             1       10                                                       2             1       10                                            Comparative                                                                               4             5       9                                             Compound 1 2             2       4                                             Comparative                                                                               4             6       6                                             Compound 2 2             2       3                                             Comparative                                                                               4             0       1                                             Compound 3 2             0       0                                             Comparative                                                                               4             0       1                                             Compound 4 2             0       0                                             ______________________________________                                    

A high level of safety was observed also in the case of the compounds of the present invention other than those presented in Tables 2 and 3.

TEST EXAMPLE 3

120 cm² pots were filled with upland field soil, and seeds of sunflower, barnyardgrass, large crab-grass, pig weed, common black jack (Bidens Pilosa), cocklebur (Xanthium Strumarium) were sown and covered with soil in a depth of from 0.5 to 1 cm, respectively. Then, a wettable powder prepared in accordance with Formulation Example 4, was diluted with 1 kl/ha of water and uniformly sprayed over the surface of soil at the dose as identified in Table 4.

Thirty six days after the treatment, the herbicidal effects were evaluated in accordance with the standards as identified in Test Example 1.

The results are shown in Table 4.

                                      TABLE 4                                      __________________________________________________________________________                   Herbicidal index                                                 Tested                                                                               Dose of active                                                                          Sun-                                                                               barnyard                                                                            Large                                                                               Pig                                                                               Common                                                                               Cock-                                    compound                                                                             ingredient (kg/ha)                                                                      flower                                                                             grass                                                                               crabgrass                                                                           weed                                                                              black jack                                                                           lebur                                    __________________________________________________________________________     Compound                                                                             4        4   10   9     7 10    10                                       5     2        0   10   7    -- 10    8                                        Compound                                                                             4        0   10   10   10 10    --                                       15    2        0   10   10   10 10    --                                       Per-  4        0    9   9     4  6    3                                        fluidone                                                                             2        0    7   8     4  6    0                                        __________________________________________________________________________      Note:-                                                                         Perfluidone is a commercially available herbicide having the following         chemical formula:                                                              ##STR31##                                                                

TEST EXAMPLE 4

A 600 cm² pot was filled with upland field soil, and seeds of barnyardgrass, large crab-grass, pig weed, lambsquater and flatsedge (Cyperus iria) were sown and covered with soil in a depth of from 0.5 to 1 cm. Then, a wettable powder prepared in accordance with Formulation Example 4, was diluted with 1 kl/ha of water and uniformly sprayed over the surface of soil at a dose of active ingredient of 1 kg/ha.

Twenty days after the treatment, the herbicidal effects were evaluated in accordance with the standards as identified in Test Example 1.

The results are shown in Tables 5 and 5'.

                  TABLE 5                                                          ______________________________________                                                Herbicidal index                                                                 Barn-    Large                                                        Tested   yard-    crab-   Pig    Lambs- Flat-                                  compound grass    grass   weed   quarter                                                                               sedge                                  ______________________________________                                         Compound 1                                                                              10       10       8     10     10                                     Compound 2                                                                              10       10      10     10     10                                     Compound 3                                                                              10       10      10     10     10                                     Compound 4                                                                              10       10      10     10     10                                     Compound 5                                                                              10       10      10      6     10                                     Compound 6                                                                              10       10      10      8     10                                     Compound 7                                                                              10        8      10     10     10                                     Compound 8                                                                              10        6      10     10     10                                     Compound 9                                                                              10       10      --     --     10                                     Compound 10                                                                             10       10       8     --     10                                     Compound 11                                                                             10        6      --     --     10                                     Compound 12                                                                             10        6      10      8     10                                     Compound 15                                                                             10       10      10     10     10                                     Compound 16                                                                             10       10      10     10     10                                     Compound 17                                                                             10       10      10      6     10                                     Compound 18                                                                             10       10      10      8     10                                     Compound 19                                                                             10       10      10     10     10                                     Compound 20                                                                             10       10       9      8     10                                     Comparative                                                                              0        0       4      6     10                                     Compound 5                                                                     Comparative                                                                              0        0        2    10     10                                     Compound 6                                                                     ______________________________________                                          ##STR32##                                                                      ##STR33##                                                                      (Compounds disclosed in U.S. Pat. No. 3,639,474)                         

                  TABLE 5'                                                         ______________________________________                                                Herbicidal index                                                                 Barn-     Large                                                       Tested   yard-     crab-   Pig    Lambs-                                                                               Flat-                                  compound grass     grass   weed   quater                                                                               sedge                                  ______________________________________                                         Compound 22                                                                             10        10      10     8     10                                     Comparative                                                                             0         0       4      6     10                                     Compound 5                                                                     Comparative                                                                             0         0       3      10    10                                     Compound 6                                                                     ______________________________________                                    

TEST EXAMPLE 5

A 600 cm² pot was filled with upland field soil, and seeds of barnyardgrass, large crab-grass, pig weed, lambsquater and flatsedge were sown and covered with soil in a depth of from 0.5 to 1 cm.

When the barnyardgrass reached a 1-leaf stage, a wettable powder prepared in accordance with Formulation Example 4, was diluted with 1 kl/ha of water and uniformly sprayed over the surface of soil at a dose of the active ingredient of 4 kg/ha.

Fourteen days after the treatment, the herbicidal effects were evaluated in accordance with the standards as identified in Test Example 1.

The results are shown in Tables 6 and 6'.

                  TABLE 6                                                          ______________________________________                                                Herbicidal index                                                                 Barn-     Large                                                       Tested   yard-     crab-   Pig    Lambs-                                                                               Flat-                                  compound grass     grass   weed   quater                                                                               sedge                                  ______________________________________                                         Compound 1                                                                              10        10      10     10    10                                     Compound 2                                                                              10        10      10     10    10                                     Compound 3                                                                              10         8      10     10    10                                     Compound 4                                                                               8         8      10     10     8                                     Compound 5                                                                              10         8      10     10    10                                     Compound 6                                                                              10         8      10     10    10                                     Compound 7                                                                               7         8      10     10    10                                     Compound 8                                                                              10         8      10     10    10                                     Compound 9                                                                               4         7      10     10    10                                     Compound 10                                                                             10        10      10     10    10                                     Compound 11                                                                              7         7       8     10    10                                     Compound 12                                                                             10        10      10     10    10                                     Compound 13                                                                             10        10       8     10    10                                     Compound 14                                                                              8         4       8     --    10                                     Compound 15                                                                              8        10      10     10    10                                     Compound 16                                                                             10         8       8      7    10                                     Compound 17                                                                             10         8      10     10    10                                     Compound 18                                                                             10        10       8      6    10                                     Compound 19                                                                             10        10      10     10    10                                     Compound 20                                                                              8         8       9      6    10                                     Comparative                                                                              2         4      10     10    10                                     Compound 5                                                                     Comparative                                                                              2         2      10     10    10                                     Compound 6                                                                     ______________________________________                                    

                  TABLE 6'                                                         ______________________________________                                                Herbicidal index                                                                 Barn-     Large                                                       Tested   yard-     crab-   Pig    Lambs-                                                                               Flat-                                  compound grass     grass   weed   quater                                                                               sedge                                  ______________________________________                                         Compound 22                                                                             10        8       10     10    10                                     Comparative                                                                             2         4       10     10    10                                     Compound 5                                                                     Comparative                                                                             2         3       10     10    10                                     Compound 6                                                                     ______________________________________                                     

What is claimed is:
 1. A trifluoromethanesulfonanilide compound having the formula: ##STR34## wherein Y is a (1-cyano-2-propyl)cyclopropyl group or a (1-cyano)cyclopentyl group.
 2. A trifluoromethanesulfonanilide compound having the formula: ##STR35## wherein Y is a (1-cyano-2-propyl)cyclopropyl group or a (1-cyano)cyclopentyl group.
 3. The compound according to claim 1, which is 2,4-dichloro-5-(1-cyano)cyclopentyltrifluoromethanesulfonanilide.
 4. The compound according to claim 1, which is 2,4-dichloro-5-(1-cyano-2-propyl)cyclopropyltrifluoromethanesulfonanilide.
 5. A herbicidal composition comprising a herbicidally effective amount of a compound of the formula I' as defined in claim 1 and an agricultural adjuvant.
 6. A method for killing weeds, which comprises applying a herbicidally effective amount of a compound of the formula I' as defined in claim 1 to a locus to be protected. 